PEDRO JOSE BARON - Academia.edu (original) (raw)

Papers by PEDRO JOSE BARON

Estuarine Coastal and Shelf Science, Jul 1, 2017

The structural patterns of the mesozooplankton community of San José Gulf (SJG), a one of a kind ... more The structural patterns of the mesozooplankton community of San José Gulf (SJG), a one of a kind semi-enclosed basin located in the northern margin of the Valdés Peninsula (Argentine Patagonia), were studied by means of semi-automatic image analysis. Samples were obtained bimonthly during the warm season (October 2012-April 2013) at stations distributed on a regular grid. Cluster analyses outlined two spatially consistent groups of stations showing similar patterns when based on physical (SST, Chl-a, and bottom depth) and

Journal of Sea Research, Apr 1, 2010

... Federico M. Ledesma a , Silvina Van der Molen b , Corresponding Author Contact Information , ... more ... Federico M. Ledesma a , Silvina Van der Molen b , Corresponding Author Contact Information , E-mail The Corresponding Author and Pedro J. Barón ... overall body shape is due to the enlargement of the branchial chambers and visceral-cavity through the ontogeny (Hines, 1982 ...

Biological Invasions, May 1, 2005

We report the finding of the European green crab on the Atlantic coast of Patagonia. A total of 6... more We report the finding of the European green crab on the Atlantic coast of Patagonia. A total of 61 specimens were found in Camarones Bay (Chubut Province, Argentina) in November 2003 and January 2004. Carapace widths ranged between 39.9 and 71.4 mm for females, and 51.4 and 81.4 mm for males. All of the females were sexually mature, and most had already spawned. Size frequency distributions and temperature conditions in the area suggest that the species had been introduced at least 3-4 years before our finding (1999-2000). The analysis of surface seawater temperature in the native and nonnative ranges of distribution of the species suggests that the crab would be able to colonize the eastern coast of South America from southern Brazil (29°S) to the mouth of the Magellan Strait (52°S). Possible areas of introduction to the region and vectors are discussed.

El alga exótica Undaria pinnatifida en Argentina Undaria pinnatifida es una macroalga parda origi... more El alga exótica Undaria pinnatifida en Argentina Undaria pinnatifida es una macroalga parda originaria del este de China, Corea, Japón y sureste de Rusia, que fue detectada en Puerto Madryn en 1992; actualmente ocupa más de 1000km de costas Patagónicas y continúa dispersándose. Undaria desarrolla anualmente una fase esporofítica que crece durante el invierno y muere en verano, y una fase gametofítica microscópica muy resistente que puede funcionar como un banco de semillas. Las densas praderas que forma la especie, y su arribazón a la costa en épocas estivales impacta fuertemente sobre los usos turísticos de las playas y los arrecifes submarinos. Recientes estudios han identificado impactos negativos sobre el ensamble de macroalgas autóctonas y sobre los peces de arrecife. Sus rangos térmicos de supervivencia son amplios aunque la esporulación sólo ocurre después de períodos con temperaturas superiores a 14ºC y la maduración de los gametofitos solo ocurre por debajo de los 20ºC. El análisis de la temperatura de la superficie del mar en las diferentes zonas portuarias de la región, y su comparación con otras regiones habitadas por Undaria sugiere que la misma podría colonizar el norte del litoral de Argentina y Uruguay.Fil: Dellatorre, Fernando Gaspar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Amoroso, Ricardo Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Baron, Pedro Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin

Estuarine, Coastal and Shelf Science

Aquaculture International, 2022

Journal of Aquatic Food Product Technology, 2020

Protein fractions and fatty acids composition, proximal composition, and quality parameters of ra... more Protein fractions and fatty acids composition, proximal composition, and quality parameters of raw Patagonian crabmeat Ovalipes trimaculatus (meat from claws and body) were analyzed. The effects of the commercial cooking processes (boiling or steaming) on total volatile base nitrogen (TVB-N) content, water-holding capacity, cooking losses, color changes, and oxidation stability were determined. Changes in physical and chemical properties and total microbial counts of boiled crabmeat (claw and body) stored at 4°C for one week were studied. The raw crabmeat showed high values of moisture and protein and a low lipid content. The pattern of all protein fractions was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) electrophoresis. Fatty acids composition was determined by gas chromatography-mass spectrometry. Polyunsaturated fatty acid (PUFA) content was approximately 75% of the total fatty acids composition, while eicosapentaenoic acid (EPA) (20:5(n-3 c)) and docosahexaenoic acid (DHA) (22:6(n-3)) were the most abundant omega-3 fatty acids. The results revealed significant differences between cooking methods. Steam-heated samples showed higher values of total volatile base nitrogen (TVB-N), pH, and cooking losses, and lower meat yield. Microbial counts and sensory analysis showed that boiled crabmeat stored at 4°C remained acceptable for consumption during 7 days of storage.

Journal of Invertebrate Pathology, 2019

Ostreid herpesvirus 1 (OsHV-1) is a DNA virus of the genus Ostreavirus (Malacoherpesviridae famil... more Ostreid herpesvirus 1 (OsHV-1) is a DNA virus of the genus Ostreavirus (Malacoherpesviridae family, Herpesvirales order). Worldwide, OsHV-1 and its microvariants have been associated with increased mortality of Pacific oysters, Crassostrea gigas. Adult asymptomatic oysters also have shown a high prevalence of viral infection. As a consequence, surveillance is needed to better describe OsHV-1 diversity, pathogenicity, clinical signs, and geographical distribution. We examined Crassostrea gigas sampled in October 2017 from the inner zone of the Bahía Blanca Estuary, Argentina, and found that 8 of 30 specimens (26.7%) presented macroscopic lesions in mantle tissues. Histological analysis revealed abnormal presentation of mantle epithelial cells and connective tissues. Conventional and real-time PCR conducted on the oyster samples revealed 70% to be positive for presence of OsHV-1 DNA. The nucleotide sequence of the amplicon obtained from one sample using the primer pair IA1/IA2 (targeting ORF 42/43) was 99% identical to OsHV-1 reference as well as µVar strains B and A (KY271630, KY242785.1), sequenced from France and Ireland. This finding represents the first detection of OsHV-1 DNA in a wild population of C. gigas in Argentina in association with gross mantle lesions.

Diseases of Aquatic Organisms, 2021

The system formed by a still-unidentified rhizocephalan infecting the Patagonian stone crab Danie... more The system formed by a still-unidentified rhizocephalan infecting the Patagonian stone crab Danielethus (Platyxanthus) patagonicus (A. Milne-Edwards, 1879) was analyzed in northern Patagonia. Out of 3222 crabs sampled, mean prevalence of externae was 2.1%, while corrected mean prevalence based on observations of externae, scars or other indicators of infection was slightly higher (3.01%; N = 2100). Prevalence was higher in males (4.47%) than in females (1.44%). Parasitized males were morphologically feminized, while females showed no hyper-feminization. Although most parasitized crabs showed only 1 externa, 2 externae were observed in some individuals. The parasite externae were only present in intermediate-sized crabs (26.6-99.7 cm carapace width). While scanning electron microscopy images allowed detection of the ‘smooth-surface-balloon’ type of retinacula on the inner surface of the externae, typical of the Sacculinidae and Peltogastridae, the position of the mantle opening relat...

Journal of South American Earth Sciences, 2018

The goal of this work was to infer the spatio-temporal patterns of bottom circulation of San José... more The goal of this work was to infer the spatio-temporal patterns of bottom circulation of San José Gulf (SJG), Patagonia, Argentina. The SJG is mainly affected by tidal circulation and presents two hydrographic domains. The Western Hydrographic Domain (WHD) presents vertically mixed waters year-round contrary to the seasonal stratified Eastern Hydrographic Domain (EHD), resulting in the formation of a thermal front between domains. Samples of sediments were collected in spring 2016 and summer 2017 at several locations to analyze the grain-size composition by means of laser diffractometry. A conceptual model of bottom hydrodynamics was inferred based on sediment`s grain-size trends. Asymmetric dominant tidal currents affect bottom sediment distribution. A general northward sediment transport is dominant at the WHD, while at the EHD there is a seasonal shift in the transport direction. There, a net northward transport with a counterclockwise gyre dominates bottom hydrodynamics at the end of the thermal front formation, conditioned by residual currents. In contrast, a net southward circulation likely driven by strong westerly winds throughout autumn and winter prevails at the beginning of the water column stratification. The inferred sediment transport suggests a net loss of material that has to be recovered by tidal currents entering through the mouth and coastal sources as runoff, mudslides, and/or aeolian dust.

Aunque la práctica de la maricultura en Argentina inicia a comienzos del siglo XX, no se ha conso... more Aunque la práctica de la maricultura en Argentina inicia a comienzos del siglo XX, no se ha consolidado ni se han producido innovaciones tecnológicas relevantes que posicionen al país competitivamente. Este estudio tiene por objetivos 1) determinar factores claves que inciden en su desarrollo, 2) medir la brecha tecnológica respecto a otros países, 3) explorar el papel estratégico de instituciones de I+D, empresas y Estado en la generación competencias innovadoras. La metodología incluyó: 1) “Análisis Morfológico” basado en el estudio de documentos previos, 2) “Análisis Semántico”, consistente en Vigilancia Tecnológica y 3) “Etapas iniciales de Prospectiva Tecnológica”, incluyendo los análisis patentométrico y cienciométrico que permiten identificar las tecnologías disponibles y emergentes a nivel mundial y un análisis de brecha. En 2009-2013, China, Francia y EEUU lideraron la producción y el desarrollo científico y tecnológico sobre cultivo de especies de interés para Argentina. L...

Marine Ecology, 2020

In biological invasion processes, changes in habitat structure induced by non-indigenous ecosyste... more In biological invasion processes, changes in habitat structure induced by non-indigenous ecosystem engineers (organisms that modify, maintain, or create a new habitat or habitat structure, Jones, Lawton, & Shachak, 1994) represent a decisive pathway of cascade effects on native communities (e.g., Burlakova,

Estuaries and Coasts, 2018

In 1981, the Pacific oyster Crassostrea (Magallana) gigas was illegally introduced for aquacultur... more In 1981, the Pacific oyster Crassostrea (Magallana) gigas was illegally introduced for aquaculture purposes in San Blas Bay located on the southern coast of Buenos Aires Province, Argentina. The presence and colonization of oysters north of Río Negro Province, 100 km to the southwest of San Blas Bay, was reported in 2005. There remains a controversy about whether or not the oyster was capable of migrating southwest to Río Negro Province from San Blas Bay, which motivates the present investigation. While one part of the local community supports that the Pacific oyster migrated naturally southwestwards reaching the northern coast of Río Negro in 2005, another faction denies this hypothesis. The aim of this work is to determine whether or not the planktonic larvae of this invasive species could have reached the mouth of Río Negro. We assume that the oyster can produce larvae after 2 years of being set on the bottom and the larvae can drift as zooplankton during 1 month. Longshore mean current was considered as the single forcing in natural transporting of oyster larvae along the coast. Shallow water wave parameters were computed from deep water wave parameters obtained from the Simulated WAves Nearshore (SWAN) model driven by NCEP/ NCAR I global reanalysis. The migration path was computed from longshore current intensities, which were estimated using the modified experimental expression given by Longuet-Higgins. Results obtained in this paper support the possibility that the Pacific oyster larvae could have arrived at Río Negro Province, between 2002 and 2005.

Estuarine, Coastal and Shelf Science, 2017

Editorial Académica Española, 2012

Scientific Reports, 2020

The southern surf crab Ovalipes trimaculatus (de Haan, 1833) presents a high potential for aquacu... more The southern surf crab Ovalipes trimaculatus (de Haan, 1833) presents a high potential for aquaculture. In this study, we analyze the benefits of different dietary treatments on its molt success and fitness of larval stages. Artemia persimilis nauplii were enriched with monospecific (Nannochloropsis oculata, Tetraselmis suecica, Dunaliella salina, Isochrysis galbana and Chaetoceros gracilis) and multispecific (Mix) microalgal diets twice a day over a 48-h period. Mean total length (TL), growth instar number (I) and gut fullness rate (GFR) of nauplii showed significant differences between dietary treatments at several sampling times, optimal results being observed in those providing Mix. Artemia nauplii grown under most experimental dietary treatments reached the capture size limit for Ovalipes trimaculatus zoea I (700 µm) within 24 h. After that time interval, Mix-enriched nauplii were amongst those with higher protein contents. Ovalipes trimaculatus zoea I fed on Artemia nauplii en...

Bulletin of Marine Science, 2018

Crustacean growth in nature is affected by hormonal processes and natural stressors. For aquacult... more Crustacean growth in nature is affected by hormonal processes and natural stressors. For aquaculture purposes, paddle crab, Ovalipes trimaculatus (De Haan, 1833), juveniles were subjected to experimental eyestalk ablation, limb removal, and a combination 3 × 3 temperature and salinity conditions. Relative lifetime in captivity (RLC), molting success (MS), molting interval (MI), growth in terms of size and weight after molting (SI and WI), specific growth rate in size (SGR s) and weight (SGR w), and hepatosomatic index (HS) were evaluated in eight replicate groups of crabs for each treatment (one crab per tank). RLC was significantly lower in eyestalk-ablated crabs than in those subjected to limb removal and to control conditions (no organ removal, 13 °C, salinity of 33); it was significantly higher in crabs held at a salinity of 30 vs those maintained at 33 and 27. Combinations of 16 or 19 °C and salinity of 30 provided the optimal conditions of growth in size and weight. Results suggest that control of temperature and salinity can improve growth and survival of juveniles in captivity. However, organ removal did not promote molting in captivity, likely to the detriment of survival and physiological condition. Findings from the present study highlight the importance of carefully selecting conditions to rear this valuable commercial crab to promote its aquaculture in the region. research paper

Canadian Journal of Zoology, 2017

An integrative analysis of sexual maturity associated with growth was developed for the spider cr... more An integrative analysis of sexual maturity associated with growth was developed for the spider crab Leurocyclus tuberculosus (H. Milne Edwards and Lucas, 1842). Sexual maturity was characterized based on gonadal, morphological, morphometric, and functional sexual maturity. Progress in sexual maturation was described through 13 growth stages (instars) detected by the examination of size (carapace width) frequency distributions. Mature females displayed mature ovaries, developed vaginae, open gonopores, allometric changes in the abdomen, and ovigerous stage in the transition from instar IX to instar X. Sexually mature males presented spermatophores in the distal vasa deferentia and allometric changes in several measurements of the right chela in the transition from instar X to instar XI. However, two prepubertal phases were recognized in both sexes separated from each other by a prepubertal critical molt. Preceding the second critical molt, gonopores were sealed and vasa deferentia sh...

Scientia Marina, 2016

The embryogenesis of Ovalipes trimaculatus, a member of the highly valued portunid swimming crabs... more The embryogenesis of Ovalipes trimaculatus, a member of the highly valued portunid swimming crabs, was studied under nearly constant temperature (13±1°C), salinity (33) and photoperiod (14 h light:10 h dark) conditions. A five-stage scale of embryonic development was defined for the species. Time required to complete development averaged 35.7±2.11 days, showing no significant differences between embryos located in inner, middle and outer portions of the egg mass. The egg chorion was rounded and showed the highest growth in diameter between stages I (morula-blastula-gastrula) and II (primordium of larval structure) and between stages III (appendage formation) and IV (eye formation). Results reported here provide a baseline for optimizing hatchery operations and useful information for management purposes.